Lap-detecting stop motion

ABSTRACT

There is disclosed a lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments. Such stop motion comprises a feeler set closely to the roll surface, the feeler in its rest or idle position being arranged substantially in a plane containing the roll axis, wherein the feeler portion nearest to the roll can be deflected in the direction of the roll circumference.

United States Patent Wuest Feb. 22, 1972 [54] LAP-DETECTING STOP MOTION[72] Inventor: Olivier Wuest, Winterthur, Switzerland [73] Assignee:Rieter Machine Works, Ltd., Winterthur,

Switzerland [22] Filed: Aug. 4, 1969 [21 Appl. No.: 847,335

[30] Foreign Application Priority Data Aug. 8, 1968 Switzerland..12119/68 [52] US. Cl ..242/36, 19/.26, 28/7l.4, 57/80, 57/86, 226/10[51] Int. Cl ..B65h 63/00 [58] field of Search ..242/36, 37, 39,18, 35,5, 242/19, 57; 226/11, 10; l9/.26; 57/80-87; 28/71.4

[56] References Cited UNITED STATES PATENTS 7/ 1927 Scott ..19/ .266/1935 McKean ..242/19 2,084,810 6/1937 Jones ..226/11 3,081,046 3/1963Barnes, Jr. et a1. ..242/36 3,169,716 2/1965 Furst ..242/36 3,512,6905/1970 Fisher et a1. ..226/11 FOREIGN PATENTS OR APPLICATIONS 952,5715/1949 France ..242/39 1,192,766 4/1959 France ..242/39 PrimaryExaminerStanley N. Gilreath Attorney-Werner W. Klieman [5 7] ABSTRACTThere is disclosed a lap-detecting stop motion for thread transportingrolls of draw-winding, drawtwisting or takeup machines'for processingendless filaments. Such stop motion comprises a feeler set closely tothe roll surface, the feeler in its rest or idle position being arrangedsubstantially in a plane containing the roll axis, wherein the feelerportion nearest to the roll can be' deflected in the direction of theroll circumference.

12 Claims, 4 Drawing Figures LAP-DETECTING STOP MOTION BACKGROUND OF THEINVENTION The present invention relates to a new and improvedlap-detecting stop motion for the thread transporting rolls ofdrawwinding, drawtwisting or takeup machines for processin endlessfilaments.

In transporting endless filaments, hereinafter conveniently referred toas threads, usually a considerable portion of the circumference of adraw roll or separator roll is covered by thread wraps, and, in case ofan end breakage or low thread tension, undesirable lap formation occursrelatively frequently, that is to say, the thread sticks to the roll andis no longer removed therefrom. This unfavorably influences theprocessing operation. The same adverse effect can occur on the takeupfriction drums on which the thread takeup package rests even if, atbest, the thread contacts the friction drum only at the contact point.

SUMMARY OF THE INVENTION Thus, a primary objective of the presentinvention is the earliest possible detection of such lap formations inorder to avoid more severe disturbances and, furthermore, stopping thethread feed as immediately as possible after detection of such lapformations.

Stop motions for this purpose are already known to the art, in which apivotable tangential feeler is set close to the roll, so that thisfeeler, in case of lap formation, is pushed aside and activates a switchwhich stops the machine. This arrangement, however, possesses the greatdisadvantage of relatively low sensitivity, activating the switch onlyif the lap already has reached a certain thickness. The triggeringdistance of the switch depends on the very small pivoting angle of thefeeler and directly on the thickness of the lap forming on the roll,such thickness is particularly very small if fine deniers are processed.

Accordingly, the present invention is primarily concerned with theachievement of the aforementioned objective and the elimination of thedisadvantages mentioned above, by means of a lap-detecting stop motionfor thread transporting rolls of draw-winding, drawtwisting or takeupmachines for processing endless filaments which is of the typecomprising a feeler positioned or set closely to the roll surface.According to an important aspect of the invention the feeler in its restor idle position is arranged substantially in a plane containing theroll axis or shaft and the feeler portion nearest to the roll can bedeflected in the direction of the roll circumference. The feeler can beconstructed in the form of a lever, wherein the portion disposed closestto the roll can, for instance, extend completely or only partially overthe width of such roll. The lever can consist of a deflectable thin,flat spring or it can be rigid.

BRIEF DESCRIPTION OF THE DRAWING The invention will be betterunderstood, and objects other than those set forth above, will becomeapparent, when con sideration is given to the following detaileddescription thereof. Such description makes reference to the annexeddrawing wherein:

FIG. 1 is a schematic view of a draw-winding machine equipped with theinventive lap detecting stop motion;

FIG. 2 shows details of the inventive lap detecting stop motion;

FIG. 3 is an alternative design of a draw'winding location or position;and

FIG. 4 is a schematic view of a drawtwisting machine equipped with theinventive lap-detecting stop motion.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawing,and, referring more particularly to FIG. I, a monoor multifilamentthread I is transferred from a suitable feed point (not shown) to a roll2 and a separator roll 3 and from there to a draw roll 4 and a separatorroll 5 both rotating faster. Then, thread 1 passes through a threadtraversing device 6 onto a bobbin 7 resting on, and driven by, a driveroll 8. Closely set to drive roll 8 is a spring or resilient plate 10deflectable in the direction of the roll circumference and mounted on ahousing 9. Spring plate 10 is connected to a switch 11 which, viacircuit 12, activates a thread cutting device 13 arranged above rolls 2and 3 if spring plate 10 is deflected upwardly into the positionindicated by dashed lines. Clearance between the surface of roll 8 andspring plate 10 is regulated by adjusting the screw 14 penetratingthrough a nonillustrated slot of plate 10. Depending on the triggeringsensitivity desired, plate 10 can be set for clearances ranging froma=0.05 to 0.1 mm. without rendering the triggering distance needed foractivation of switch 11 too small. For obtaining optimum performance itis advantageous if plate 10 is arranged in, or as closely as possibleto, a plane comprising the axis or shaft of the roll on which laps areto be detected.

As an example, it can be stated that for a triggering distance it (FIG.2) of switch 11 of approximately I mm., total deflection h of the plate10 on the drive roll must be about 2 mm. At a draw roll diameter of R=50mm. and a plate length of r=40 mm. to the pivoting point D correspondingto the position of screw 14 a deflection h results if thread wraps arewound to a thickness of S=0.07 mm. It can be seen from this that a verysmall thread lap thickness of S=0.07 causes a deflection of the plate onthe roll which corresponds to about 17 times the small lap thickness,plate clearance being a=0.05 mm. This plate deflection can be used toactivate a switch, as explained above. The formation of an undesirablelap thus can be suppressed at its very beginning if the threadimmediately is cut by means of cutting device 13, i.e., if thread feedis stopped. As best seen by referring to FIG. 2, a pivotal rigid lever10' pivotably arranged about an axis or shaft D can be substituted foran elastic thin plate 10, this rigid lever 10 can be constructed to becompletely flat or only at its end confronting the roll.

The arrangement according to FIG. 3 differs from the one shown in FIG. Ionly in that here the thread after passing through the traversing threadguide 15 encircles about half the circumference of drive roll 16 beforebeing wound onto bobbin 17. If a lap-detecting stop motion device 18,reacting fast as described above, is provided at the region of the driveroll 16 covered by the thread, the traversing thread guide 15 can bearranged very closely to drive roll 16 without danger of damage in caseof lap formation. The particular advantage, however, is the possibilityof keeping to a minimum the distance F between the traversing threadguide 15 and the thread takeup point A, as the shape of the packageimproves the closer to the takeup point A thread traversing is effected.In a winding unit without a lap detecting stop motion, or one whichreacts only after a considerable lap thickness is built up, thetraversing thread guide would have to be located farther away anddistance F necessarily would increase so much that package build wouldbe impaired. Arrangement of a lap-detecting stop motion at drive rolls 8or 16 is of particular advantage as these rolls are the last elements inthe thread path on which lap formation possibly can occur.

In drawtwisting machines, such as exemplified in FIG. 4, the lapdetection device 19 of course must be arranged at draw roll 20, asshown, as here no lapping occurs on spindle 21, and at which thearrangement of a detecting device would not make sense. 1

Also, on a draw-winding machine according to FIGS. 1 and 3, thearrangement of an additional detecting device 22 (indicated with phantomor dashed lines in FIG. 1) at draw roll 4 can be considered, in order toalso immediately detect laps forming there. This device is wiredparallel into circuit 12.

It should be apparent from the foregoing detailed description that theobjects set forth at the outset to the specification have beensuccessfully achieved.

What is claimed is:

l. A lap-detecting stop motion for thread transporting rolls ofdraw-winding, drawtwisting or takeup machines for processing endlessfilaments, comprising a thread transporting roll, a feeler set closelyto the roll surface, said feeler in its rest position being arrangedsubstantially in a plane containing the roll axis, means mounting saidfeeler such that the feeler portion nearest to the roll surface iscapable of deflecting in a direction along at least part of the rollcircumference, separate cutting means arranged in spaced relationshipfrom said feeler for cutting the thread upon lap formation at the threadtransporting roll, and means operatively connecting said cutting meanswith said feeler for actuating said cutting means in response todetection of lap formation at said roll by said feeler.

2. A lap-detecting stop motion according to claim 1, wherein said feeleris in the form ofa lever,

3. A lap-detecting stop motion according to claim wherein said feelercomprises a thin spring plate.

4. A lap-detecting stop motion according to claim 2, wherein said leveris pivotably arranged on a fixed axis.

5. A lap-detecting stop motion according to claim 1, wherein saidoperatively connecting means includes an electric circuit, an electricswitch for influencing said electric circuit, said feeler beingoperatively connected to said electric switch so that when said feeleris deflected said electric switch influences said electric circuit.

6. A lap-detecting stop motion according to claim 1, wherein said feeleris arranged at a thread package drive roll ofa draw-winding machine.

7. A lap-detecting stop motion according to claim 6, wherein said feeleris arranged at a portion of said drive roll transferring the thread tothe thread package in the region which is covered by the thread 8. Alap-detecting stop motion according to claim I, wherein said feeler isarranged at a draw roll.

9. A lap-detecting stop motion according to claim 1, wherein said feeleris in the form of a lever, said lever possessing a substantially flatconstruction at the region of said feeler portion nearest the roll.

10. A lap-detecting stop motion according to claim 1. wherein saidfeeler is in the form of a lever, means providing a pivot point for saidlever which is located substantially in said plane containing the rollaxis.

11. A lap-detecting stop motion for thread transporting rolls ofdraw-winding, drawtwisting or takeup machines for processing endlessfilaments, comprising a thread transporting roll, a substantially flat,lightweight, quickly responsive feeler arranged closely to the rollsurface, said feeler in its rest position being located substantially ina plane containing the roll axis, means mounting said feeler such thatthe feeler portion nearest to the roll surface is capable of deflectionalong at least a portion of the circumference of the roll, cutting meansarranged in spaced relationship from said feeler for cutting the threadupon the formation of laps at the thread transporting roll irrespectiveof the position of the thread at the surface of such roll, and meansoperatively connecting said cutting means with said feeler for actuatingsaid cutting means in response to detection of lap formation at saidroll surface by said feeler.

12. A lap-detecting stop motion according to claim 11, further includinga traversing thread guide located in close proximity to said roll fordelivering thread thereto.

1. A lap-detecting stop motion for thread transporting rolls ofdraw-winding, drawtwisting or takeup machines for processing endlessfilaments, comprising a thread transporting roll, a feeler set closelyto the roll surface, said feeler in its rest position being arrangedsubstantially in a plane containing the roll axis, means mounting saidfeeler such that the feeler portion nearest to the roll surface iscapable of deflecting in a direction along at least part of the rollcircumference, separate cutting means arranged in spaced relationshipfrom said feeler for cutting the thread upon lap formation at the threadtransporting roll, and means operatively connecting said cutting meanswith said feeler for actuating said cutting means in response todetection of lap formation at said roll by said feeler.
 2. Alap-detecting stop motion according to claim 1, wherein said feeler isin the form of a lever.
 3. A lap-detecting stop motion according toclaim 1, wherein said feeler comprises a thin spring plate.
 4. Alap-detecting stop motion according to claim 2, wherein said lever ispivotably arranged on a fixed axis.
 5. A lap-detecting stop motionaccording to claim 1, wherein said operatively connecting means includesan electric circuit, an electric switch for influencing said electriccircuit, said feeler being operatively connected to said electric switchso that when said feeler is deflected said electric switch influencessaid electric circuit.
 6. A lap-detecting stop motion according to claim1, wherein said feeler is arranged at a thread package drive roll of adraw-winding machine.
 7. A lap-detecting stop motion according to claim6, wherein said feeler is arranged at a portion of said drive rolltransferring the thread to the thread package in the region which iscovered by the thread.
 8. A lap-detecting stop motion according to claim1, wherein said feeler is arranged at a draw roll.
 9. A lap-detectingstop motion according to claim 1, wherein said feeler is in the form ofa lever, said lever possessing a substantially flat construction at theregion of said feeler portion nearest the roll.
 10. A lap-detecting stopmotion according to claim 1, wherein said feeler is in the form of alever, means providing a pivot point for said lever which is locatedsubstantially in said plane containing the roll axis.
 11. Alap-detecting stop motion for thread transporting rolls of draw-winding,drawtwisting or takeup machines for processing endless filaments,comprising a thread transporting roll, a substantially flat,lightweight, quickly responsive feeler arranged closely to the rollsurface, said feeler in its rest position being located substantially ina plane containing the roll axis, means mounting said fEeler such thatthe feeler portion nearest to the roll surface is capable of deflectionalong at least a portion of the circumference of the roll, cutting meansarranged in spaced relationship from said feeler for cutting the threadupon the formation of laps at the thread transporting roll irrespectiveof the position of the thread at the surface of such roll, and meansoperatively connecting said cutting means with said feeler for actuatingsaid cutting means in response to detection of lap formation at saidroll surface by said feeler.
 12. A lap-detecting stop motion accordingto claim 11, further including a traversing thread guide located inclose proximity to said roll for delivering thread thereto.